Moisture management systems and methods for building openings

ABSTRACT

Moisture management systems and methods are provided for managing moisture in a vicinity of an opening in a building wall. Such systems comprise a sill pan mountable in the building wall atop a horizontally-extending lower frame member of the opening. The sill pan may include: a base section having an upper surface which slopes downwardly and outwardly from a location interior to a lower flange portion of a window frame to an interstitial space between a sheathing layer of the building wall and an external building wall layer for directing moisture received thereon toward the interstitial space; and a plurality of transversely spaced-apart window-support members having upper surfaces located above the upper surface of the base section and oriented substantially horizontally for receiving a lower portion of the window frame. Such systems also comprise a lower vent mountable in the building wall outwardly of the sill pan. The lower vent may include: a vent component which defines a plurality of apertures that provide fluid communication between an exterior of the building wall and the interstitial space; and a hood shaped to extend downwardly and outwardly from a location above the apertures in the vent component and interior to the exterior building wall layer to a location external to the building wall.

TECHNICAL FIELD

The invention relates to moisture management systems for building openings in walls or the like. Particular embodiments provide moisture management systems for window openings.

BACKGROUND

Excess moisture and/or moisture buildup can damage building walls. These problems are particularly prevalent in humid and/or damp environments. Openings in building walls, such as window openings for example, are particularly problematic regions in which moisture tends to accumulate. Openings in building walls also tend to provide regions where moisture can enter an interior of building wall and/or can move from the interior of a building to the exterior of a building or vice versa.

There is a general desire to provide systems and methods for managing moisture in and around openings in building walls.

SUMMARY

Aspects of the present invention provide apparatus and methods for managing moisture in a vicinity of an opening in a building wall.

One particular aspect of the invention provides an apparatus for managing moisture in a vicinity of an opening in a building wall. The apparatus comprises a sill pan and a lower vent for managing moisture in a vicinity of a lower perimeter of the opening. The sill pan is mountable in the building wall atop a horizontally-extending lower frame member of the opening. The comprises a base section having an upper surface which slopes downwardly and outwardly from interior to a sheathing layer of the building wall to an interstitial space between the sheathing layer and an external building wall layer for directing moisture received thereon toward the interstitial space. The lower vent is mountable in the building wall in a vicinity of the lower perimeter of the window opening. The lower vent comprises: a vent component which defines a plurality of lower vent apertures that provide fluid communication between an exterior of the building wall and the interstitial space; and a hood shaped to extend downwardly and outwardly from above the lower vent apertures and from interior to the exterior building wall layer to the exterior of the building wall.

Another aspect of the invention provides an apparatus for managing moisture in a vicinity of a window opening in a building wall. The apparatus comprises a pair of corner components and a connector component. Each corner component comprises: a corner base section mountable atop a horizontally-extending lower frame member of the opening and having an upper surface which slopes downwardly and outwardly from interior of a sheathing layer of the building wall to an interstitial space between the sheathing layer and an external building wall layer for directing moisture received thereon toward the interstitial space; a plurality of transversely spaced-apart corner window support members having upper surfaces located above the upper surface of the corner base section and oriented substantially horizontally for receiving a lower portion of a window frame; a corner exterior flange extending downwardly from the corner base section and abutting against an exterior surface of sheathing layer; and a plurality of transversely spaced-apart corner spacers having exterior surfaces that are located exterior to an exterior surface of the corner exterior flange and wherein at least a portion of the window frame abuts against the exterior surfaces of the corner spacers. The connector component connects the corner components to one another and comprises a connector base section and a pair of wings that extend from the connector base section in transversely opposing directions to form snap-together couplings between a corresponding one of the wings and one or more notches on each of the corner components.

Another aspect of the invention provides a method for managing moisture in a vicinity of a window opening of a building wall. The method comprises: creating an interstitial space between a sheathing layer of the building wall and an external building wall layer; mounting a sill pan in the building wall atop a horizontally-extending lower frame member of the window opening, the sill pan comprising: a base section having an upper surface which slopes downwardly and outwardly from a location interior to the sheathing layer to the interstitial space for directing moisture received thereon toward the interstitial space; and a plurality of transversely spaced-apart window-support members having substantially horizontally oriented upper surfaces located above the upper surface of the base section; installing a window in the window opening such that at least part of a lower portion of the window frame is positioned atop the upper surfaces of the window-support members; mounting a lower vent in the building wall in a vicinity of a lower perimeter of the window opening, the lower vent comprising: a vent component which defines a plurality of lower vent apertures that provide fluid communication between an exterior of the building wall and the interstitial space; and a hood shaped to extend downwardly and outwardly from above the lower vent apertures and from interior to the exterior building wall layer to the exterior of the building wall; and applying the external building wall layer to the building wall, the external building wall layer overlapping a lower portion of the vent component below the lower vent apertures.

BRIEF DESCRIPTION OF THE DRAWINGS

In drawings which depict non-limiting embodiments of the invention:

FIG. 1 is a partially cut-away, exterior isometric view of a sill pan assembly of a moisture management system according to a particular embodiment of the invention disposed in an opening of a building wall;

FIGS. 2A, 2B and 2C (collectively, FIG. 2) are isometric views of a left corner component, a right corner component and a connector component of the FIG. 1 sill pan assembly;

FIGS. 3A and 3B (collectively FIG. 3) are partially cut-away, interior isometric views of the FIG. 1 sill pan disposed in a window opening of a building wall;

FIG. 4 is a partially cut-away, exterior isometric view of the FIG. 1 sill pan assembly without the connector component;

FIG. 5 is an isometric view of a lower vent assembly of a moisture management system according to a particular embodiment of the invention disposed adjacent to the lower perimeter of an opening in a building wall;

FIGS. 6A-6C (collectively FIG. 6) are isometric views of the various components of the FIG. 5 lower vent assembly;

FIG. 7 is a cross-sectional view showing portions of the FIG. 5 lower vent assembly and the FIG. 1 sill pan assembly installed in a building wall;

FIGS. 8A-8J are isometric views which show a method for installing the FIG. 1 sill pan assembly, the FIG. 5 lower vent assembly and the FIG. 9 upper vent assembly into a building wall around an opening thereof;

FIG. 9 is a partially cut-away view of an upper vent assembly of a moisture management system according to a particular embodiment of the invention installed adjacent to the upper perimeter of an opening in a building wall;

FIGS. 10A, 10B and 10C (collectively, FIG. 10) are isometric views of the various components of the FIG. 9 upper vent assembly; and

FIG. 11 is a cross-sectional view showing portions of the FIG. 9 upper vent assembly installed in a building wall.

DETAILED DESCRIPTION

Throughout the following description, specific details are set forth in order to provide a more thorough understanding of the invention. However, the invention may be practiced without these particulars. In other instances, well known elements have not been shown or described in detail to avoid unnecessarily obscuring the invention. Accordingly, the specification and drawings are to be regarded in an illustrative, rather than a restrictive, sense.

Aspects of the invention provide moisture management apparatus and methods for draining and/or venting moisture away from window openings. Particular aspect of the invention combine: a sill pan assembly which protects a window sill by draining moisture away from the window sill toward an interstitial space between the sheathing layer and the external layer of a building wall; a lower vent assembly for providing fluid communication between the exterior of a building wall and the interstitial space below the window; and an upper vent assembly for providing fluid communication between the exterior of the building wall and the interstitial space above the window.

FIGS. 1-11 depict various components of a moisture management system 100 according to a particular embodiment of the invention. Moisture management system 100 comprises a sill pan assembly 10 (FIG. 1) which, in the illustrated embodiment, is disposed on a horizontally-extending lower interior frame member 102 of building opening 104. In the illustrated embodiment, building opening 104 is a window opening, although the invention may generally be used in connection with any building opening.

Typically, window opening 104 is formed in a building wall 106. Horizontally-extending lower interior frame member 102 is often referred to as window “sill” 102. In the illustrated embodiment, sill pan assembly 10 comprises a left corner component 11A (FIG. 2A) and a right corner component 11B (FIG. 2B) which are coupled together by a connector component 30 (FIG. 2C). In particular embodiments, corner components 11A, 11B (together, corner components 11) and connector component 30 are fabricated from plastic or some other moisture-resistant material. Corner components 11 and connector component 30 may be fabricated by an injection molding process, for example.

Left and right corner components 11A, 11B are mirror images of one another. As shown in FIGS. 2A and 2B, left and right corner components 11A, 11B respectively comprise: downwardly-extending exterior flanges 12A, 12B (together downwardly-extending exterior flanges 12); upwardly-extending exterior flanges 13A, 13B (together upwardly-extending exterior flanges 13); base sections 14A, 14B (together, base sections 14); and side flanges 15A, 15B (together side flanges 15).

This description employs a number of simplifying directional conventions. Directions are described in relation to a vertical building wall (e.g. wall 106 of FIG. 1). Referring to FIG. 1, directions may be referred to as: “external”, “outward” or the like if they tend toward the exterior 108 of building wall 106; “internal”, “inward” or the like if they tend toward the interior 110 of building wall 106; “upward” or the like if they tend toward the top (not explicitly enumerated) of building wall 106; “downward” or the like if they tend toward the bottom (not explicitly enumerated) of building wall 106; “vertical” or the like if they tend both upwardly and downwardly; “leftward” or the like if they tend toward one side of building wall 106; “rightward” or the like if they tend toward the opposing side of building wall 106; and “sideways”, “transverse” or the like if they tend both leftward and rightward. It will be appreciated by those skilled in the art that these directional conventions are used for the purpose of facilitating the description and should not be interpreted in a literal sense. In particular, the invention may be employed, for example, in walls 106 that are not strictly vertically oriented.

Sill pan assembly 10 may be installed in window opening 104 of wall 106 by positioning corner components 11 on sill 102 such that side flanges 15 abut against left and right vertically-extending interior frame members 112A, 112B (together vertically-extending interior frame members 112) of wall 106 (FIG. 3B). In some applications, the exterior surfaces of frame members 112 may be covered by a sheathing layer 120 as discussed in more detail below. Sheathing layer 120 may comprise plywood, building paper (e.g. Tyvek™ or the like), other building wrap material(s), other moisture barrier material(s) and/or the like. In such applications, upwardly-extending exterior flanges 13 and/or side flanges 15 may abut against the sheathing material. In other applications, sheathing layer 120 may not be present or may not cover the exterior surfaces of frame members 112. In such applications, upwardly-extending exterior flanges 13 may abut directly against the exterior surfaces of frame members 112.

In the illustrated embodiment, upwardly-extending exterior flanges 13 comprise channels 16A, 16B (together, channels 16—FIGS. 2A, 2B) through which suitable fasteners (e.g. nails, screw or the like (not explicitly shown)) may project to fasten corner components 11 to vertically-extending interior frame members 112. Channels 16 may permit shape changes and/or movement of corner components 11 and/or wall 106 (e.g. due to aging, temperature changes, drying of the wooden frame or the like). In some embodiments, similar channels may be provided on side flanges 15. Channels 16 are not necessary. In some embodiments, suitable fasteners (e.g. nails, screws, staples or the like) may project directly through any of flanges 13, 15 for mounting corner components 11 to wall 106. In other embodiments, fasteners are not required and suitable adhesive may be used to mount corner components 11 to wall 106.

Side flanges 15 and upwardly-extending exterior flanges 13 combine to abut against the lower corners of window opening 104 with base sections 14 extending leftward or rightward from their respective side flanges 15 toward a center of window opening 104. As best seen in FIG. 2B, corner components 11 comprise wedge-shaped legs 19A, 19B (together, legs 19) which, when corner components 11 are installed, extend downwardly from base sections 14 provide space between undersurfaces 21A, 21B (together, undersurfaces 21) of base sections 14 and sill 102. This space between undersurfaces 21 and sill 102 permits moisture to escape from sill 102 (e.g. natural moisture which may be contained in sill 102 when it is made of wood). Base sections 14 are integrally formed with side flanges 15 and with upwardly-extending exterior flanges 13 to prevent moisture seepage in the lower corners of window opening 104 which may result from any joints therebetween. In the illustrated embodiment, as shown best in FIG. 2B, side flanges 15 comprise lower edges 23A, 23B (together, lower edges 23) which extend below base sections 14 and which have a shape similar to that of legs 19.

Legs 19 of base sections 14 are wedge-shaped such that when corner components 11 are set atop window sill 102, the upper surfaces 17A, 17B (together, upper surfaces 17) of base sections 14 slope downwardly and outwardly to direct moisture received thereon away from interior 110 of building wall 106. In the illustrated embodiment, upper surfaces 17 also comprise optional transversely and vertically-extending steps 18A, 18B (together, steps 18—FIGS. 2A, 2B) which further prevent moisture received on an external side of steps 18 from moving toward an interior side of steps 18.

Base sections 14 also comprise pluralities of transversely spaced apart window-support members 20A, 20B (collectively, window-support members 20) which extend inwardly/outwardly and vertically from upper surfaces 17. Window-support members 20 comprise upper surfaces 22A, 22B (collectively, upper surfaces 22—FIGS. 2A, 2B). At least portions of upper surfaces 22 are shaped to be oriented generally parallel to sill 102 (e.g. horizontal in the illustrated drawings). Upper surfaces 22 may also comprise notches 24A, 24B (collectively, notches 24—FIGS. 2A, 2B). As explained in more detail below, upper surfaces 22 of window-support members 20 receive a lower window frame portion 101C and ensure that window 107 is resting on a substantially level (e.g. horizontal) surface.

Downwardly-extending exterior flanges 12 extend downwardly from base sections 14. Preferably, downwardly-extending exterior flanges 12 are integrally formed with base sections 14 to prevent moisture seepage in the lower portion of window opening 104 which may result from any joints therebetween. Downwardly-extending exterior flanges 12 may abut against window sill 102 and optionally may extend leftwardly/rightwardly to abut against vertically-extending interior frame members 112. In applications where sill 102 and/or frame members 112 are covered by sheathing layer 120, downwardly-extending exterior flanges 12 may abut against the sheathing material. The exterior surface of downwardly-extending exterior flanges 12 comprise a plurality of transversely spaced apart spacers 26A, 26B (collectively, spacers 26—FIGS. 2A, 2B) which extend outwardly and vertically therefrom. In the illustrated embodiment, the transverse spacing of spacers 26 is the same as that of window-support members 20, although this is not necessary. Spacers 26 may extend upwardly to meet window-support members 20 at the junction between base sections 14 and downwardly-extending exterior flanges 12.

Corner components 11 may be fabricated in a number of standard sizes. During installation in window opening 104, corner components 11 may be cut to appropriate lengths (FIG. 4) such that after installation of corner components, a space 28 is provided therebetween. Connector component 30 (FIG. 1C) may then be used to couple corner components 11 to one another. Connector component 30 incorporates leftwardly and rightwardly extending wing members 31A, 31B (together, wing members 31). Each of left and right wing members 31A, 31B are respectively sized to matingly fit within notches 24 in window-support members 20 of left and right corner components 11A, 11B. In the illustrated embodiment, each of window-support members 20 comprises a corresponding notch 24. This is not necessary. In some embodiments, only a subset of window-support members 20 closest to the center of window opening 104 are provided with notches 24, so that corner components 11 can be cut to length and may still be coupled to one another by connector component 30.

In particular embodiments, wing members 31 fit into notches 24 via “snap-together” coupling. Such snap-together coupling may involve deformation of wing members 31 and/or notches 24. Although not explicitly shown in the illustrated embodiments, the surfaces of wing members 31 and/or notches 24 may be provided with suitable surface features (e.g. protrusions and/or indents) and/or with suitable shapes (e.g. angled profiles) which facilitate snap-together coupling.

Connector component 30 comprises a base section 32 which sits atop window sill 102. In the illustrated embodiment, base section 32 comprises a wedge-shaped leg 33 (FIG. 3) which may fit in space 28 to abut against window sill 102, such that when connector component 30 is coupled to corner components 11, an upper surface 34 of base section 32 slopes downwardly and outwardly to direct moisture received thereon away from interior 110 of building wall 106. In the illustrated embodiment, upper surface 34 also comprises optional transversely and vertically-extending step 36 (FIG. 2C) which further prevents moisture received on an external side of step 36 from moving toward an interior side of steps 36.

Connector component 30 may also incorporate one or more window-support members 38 (FIG. 2C) which extend inwardly/outwardly and vertically from upper surface 34. Window-support members 38 comprise upper surfaces 40 (FIG. 2C). At least portions of upper surfaces 40 are shaped to be oriented generally parallel to sill 102 (e.g. horizontal in the illustrated drawings). Preferably, window-support members 38 are shaped such that, when connector component 30 is used to coupled corner components 11 to one another, these generally parallel portions of upper surfaces 40 are coplanar with the corresponding generally parallel portions of upper surfaces 22 of window-support members 20. In the illustrated embodiment, wings 31 are shaped such that when wings 31 are coupled to corner components 11, the upper surfaces 42A, 42B (together, upper surfaces 42—FIG. 2C) of wings 31 are substantially coplanar with the generally parallel portions of the upper surfaces 22, 40 of window-support members 20, 38.

Connector component 30 also comprises a downwardly-extending exterior flange 44 which extends downwardly from base section 32. Preferably, downwardly-extending exterior flange 44 is integrally formed with base section 32 to prevent moisture seepage in the lower portion of window opening 104 which may result from any joints therebetween. Downwardly-extending exterior flange 44 may be shaped to provide an interior portion (not explicitly shown in the illustrated views) which abuts against window sill 102 in the region of space 28. In applications where the exterior side of sill 102 is covered by sheathing layer 120, then the interior portion of downwardly-extending exterior flange 44 may abut against the sheathing material. Downwardly-extending exterior flange 44 may be shaped such that, when connector component 30 couples corner components 11, an exterior surface 46 of downwardly-extending exterior flange 44 is substantially coplanar with the exterior surfaces of spacers 26.

Moisture management system 100 may also comprise a lower vent assembly. FIG. 5 shows a lower vent assembly 50 according to a particular embodiment of the invention disposed adjacent a lower perimeter of opening 104 in building wall 106. FIGS. 6A-6C depict the various components of a lower vent assembly 50 according to a particular embodiment of the invention. FIG. 7 is a cross-sectional view showing portions of lower vent assembly 50 and sill pan assembly 10.

In the illustrated embodiment, lower vent assembly 50 comprises a vent component 52 which extends transversely between optional left and right side components 54A, 54B (together, side components 54). In particular embodiments, vent component 52 and side components 54 are fabricated from plastic or some other moisture-resistant material. Vent component 52 and side components 54 may be fabricated by an injection molding process, for example.

Vent component 52 is preferably a single monolithic component which extends transversely between side components 54. Vent component 52 comprises a hood 63. In the illustrated embodiment, hood 63 incorporates an upper hood portion 56 and an external hood portion 60. Upper hood portion 56 extends transversely between side components 54. In the illustrated embodiment, when lower vent assembly 50 is installed in wall 106, an interior edge 58 of upper hood portion 56 abuts against lower window flange 103C of lower window frame 101C. As shown in FIG. 7, lower window flange 103C of lower window frame 101C may extend downwardly between interior edge 58 of upper hood portion 56 and the exterior surfaces of spacers 26. In the illustrated embodiment, upper hood portion 56 extends outwardly and optionally downwardly from interior edge 58 to direct moisture received thereon away from interior 110 of building wall 106.

In the illustrated embodiment, hood 63 of vent component 52 also comprises an external hood portion 60 which extends transversely between side components 54. When lower vent assembly 50 is installed in wall 106, external hood portion 60 extends downwardly and optionally outwardly from upper hood portion 56 to direct moisture received thereon away from interior 110 of building wall 106. To the extent that upper hood portion 56 and external hood portion 60 both extend downwardly and outwardly, external hood portion 60 extends more sharply downwardly than upper hood portion 56. As shown in FIG. 7, hood 63 may be shaped and/or located such that a lower-outward edge 65 of hood 63 (i.e. a lower-outward edge of external hood portion 60) is located further outwardly than external wall layer 118 (e.g. siding or the like). In some embodiments, upper hood portion 56 may extend outwardly to a location outward of external wall layer 118, such that all of external hood portion 60 is located outwardly of external wall layer 118. Lower-outward edge 65 of hood 63 may also be located below venting apertures 72 discussed further below.

Hood 63 tends to direct moisture, such as from rain or snow, toward exterior 108 of building wall 106 and to prevent such moisture from entering interstitial space 116 between external wall layer 118 and sheathing layer 120 of building wall 106 as explained in more detail below.

Hood 63 may also comprise an optional drip flange 62. In the illustrated embodiment, where hood 63 comprises upper hood portion 56 and external hood portion 60, drip flange 62 extends transversely between side components 54 at a lowermost end of external hood portion 60. Drip flange 62 also extends downwardly and outwardly. To the extent that upper hood portion 56 and external hood portion 60 both extend downwardly and outwardly, external hood portion 60 extends more sharply downwardly than drip flange 62 and drip flange 62 extends more sharply downwardly than upper hood portion 56.

Vent component 52 also comprises a vent flange 64 which depends downwardly from upper hood portion 56 at a location spaced outwardly from interior edge 58 and which extends transversely between side components 54. Vent flange 64 comprises a plurality of apertures 72 which provide fluid communication (e.g. air flow) between interstitial space 116 and exterior 108 of building wall 106, as explained in more detail below. In the illustrated embodiment, vent flange 64 comprises an upper venting portion 68 and a lower mounting portion 66. When lower vent assembly 50 is installed in building wall 106, at least a portion of upper venting portion 68 is preferably located below window sill 102 and above the uppermost extent of external wall layer 118 (e.g. siding) below window opening 104. With this position of lower vent assembly 50, at least some of apertures 72 in upper venting portion 68 are located to provide fluid communication between interstitial space 116 and exterior 108 of wall 106.

Lower mounting portion 66 extends further downwardly from upper venting portion 68. Lower mounting portion 66 may extend downwardly on an interior of an uppermost portion of external wall layer 118 below window opening 104. Lower mounting portion 66 may comprise apertures 74 through which suitable fasteners (e.g. nails, screw or the like (not explicitly shown)) may project to fasten vent component 52 to an exterior lower frame member 134B or to external wall layer 118. Apertures 74 are not necessary. In some embodiments, suitable fasteners (e.g. nails, screws, staples or the like) may project directly through lower mounting portion 66 into exterior lower frame member 134B or external wall layer 118. In still other embodiments, fasteners are not required and suitable adhesive or the like may be used between lower mounting portion 66 and exterior lower frame member 134B or external wall layer 118.

Vent flange 64 may comprise an optional offset step 70 between lower mounting portion 66 and upper venting portion 68 such that lower mounting portion 66 is located inwardly from upper venting portion 68. Optional offset step 70 may help to maintain the width of interstitial space 116 in the region of sill pan assembly 10, such that air flow through apertures 72 into and out of interstitial space 116 is not restricted in this region. As shown in FIG. 7, offset step 70 may also allow upper venting portion 68 to be located outwardly of the interior surface of external building layer 118.

Lower vent assembly 50 also comprises optional side components 54. Side components 54 comprise mounting flanges 76A, 76B (together, mounting flanges 76) which may be installed to abut against exterior vertically-extending frame members 122, as explained in more detail below. Projections 77A, 77B (together, projections 77) and projections 79A, 79B (together, projections 79) project sideways from mounting flanges 76 toward the center of window opening 104. As shown best in FIG. 6B, projections 77 provide channels 78A, 78B (together, channels 78) which may respectively receive the left and right ends of hood 63 of vent component 52. In addition, upper venting portion 68 of vent flange 64 of vent component 52 may abut against an exterior side of projection 79. In particular embodiments, vent component 52, which has a uniform cross-section, may be provided in standard lengths and then cut to an appropriate size for fitting between side components 54 in wall 106.

Moisture management system 100 may also comprise an upper vent assembly. FIGS. 9 and 11 shows an upper vent assembly 200 according to a particular embodiment of the invention disposed adjacent to an upper perimeter of opening 104 in building wall 106. FIGS. 10A, 10B and 10C show the various components of upper vent assembly 200. Upper vent assembly 200 comprises a vent component 202 which extends transversely between a pair of optional side components 216A, 216B (together, side components 216). In particular embodiments, vent component 202 and side components 216 are fabricated from plastic or some other moisture-resistant material. Vent component 202 and side components 216 may be fabricated by an injection molding process, for example. Upper vent assembly 200 may be installed above window opening 104 for draining moisture away from the top of window opening 104 and for venting interstitial space 116 above window opening 104.

Vent component 202, which is preferably fabricated from a single monolithic piece of material, comprises hood 203, mounting flange 205 and vent portion 211 which extend transversely between side components 216 to provide a substantially uniform cross-section. When upper vent assembly 200 is installed in building wall 106 (FIGS. 9 and 11), hood 203 extends outwardly and downwardly to direct moisture received thereon toward an exterior 108 of building wall 106. Hood 203 protects against the possibility of moisture, such as from rain or snow, entering building wall 106 at the top of window opening 104. Hood 203 may be shaped and/or located such that a lower-outward edge 207 of hood 203 (FIG. 9) is located further outwardly than external wall layer 118. In the illustrated embodiment, hood 203 comprises a upper hood potion 204 and optional drip flange 206. Upper hood portion 204 extends outwardly and optionally downwardly while drip flange 206 extends downwardly and optionally outwardly. To the extent that upper hood portion 204 and drip flange 206 both extend outwardly and downwardly, drip flange 206 extends more sharply downwardly than upper hood portion 204.

In the illustrated embodiment, mounting flange 205 comprises an upper flange portion 226 and a lower flange portion 208, both of which extend vertically and transversely between side components 216. In the illustrated embodiment, mounting flange 205 comprises a step 212 (FIG. 10B) for offsetting lower flange portion 208 outwardly from upper flange portion 226. Step 212 allows extra space for window flange 103A of upper window frame 101A to be located inwardly of lower flange portion 208 (FIG. 11). Step 212 is not required. In other embodiments, upper flange portion 226 and lower flange portion 208 may be substantially coplanar.

Upper flange portion 226 may comprise apertures 214 through which suitable fasteners (e.g. nails, screw or the like (not explicitly shown)) may project to fasten vent component 202 to sheathing layer 120 as explained in more detail below. Apertures 214 are not necessary. In some embodiments, suitable fasteners (e.g. nails, screws, staples or the like) may project directly through upper flange portion 226 into sheathing layer 120. In some embodiments, suitable adhesive may be used to mount vent component 202 to sheathing 120. Lower flange portion 208 may comprise a stand-off portion 209 which extends below the intersection of hood 203 and flange 205. When upper vent assembly 200 is installed in window opening 104 (FIG. 11), stand off portion 209 may be placed on upper window frame 101A and may abut against upper window flange 103A of upper window frame portion 101A. An undersurface of hood 203 may also be placed atop upper window frame 101A to ensure that hood portion 203 extends downwardly and outwardly for directing moisture as discussed above.

Vent portion 211 extends outwardly from flange 205 at a location above hood 203. Vent portion 211 is penetrated by a plurality of apertures 210 which, when upper venting assembly 200 is installed in window opening 104, allow air flow to interstitial space 116 of wall 106 between sheathing layer 120 and external building layer 118 (FIG. 11). This air flow provides venting which tends to remove moisture from interstitial space 116 above window opening 104. In the illustrated embodiment, vent portion 211 also comprises an optional downwardly extending flange 213. External building layer 118 may abut against downwardly extending flange 213 when upper venting assembly 200 is installed in window opening 104.

Upper vent assembly 200 also comprises side components 216 (FIG. 10C). Side components 216 comprise mounting flanges 218A, 218B (together, mounting flanges 218) which may be installed to abut against exterior vertically-extending frame members 122, as explained in more detail below. Projections 220A, 220B (together, projections 220) and projections 224A, 224B (together, projections 224) project sideways from mounting flanges 218 toward the center of window opening 104. As shown best in FIG. 10C, projections 220, 224 provide channels 222A, 222B (together, channels 222) which may respectively receive the left and right ends of hood 203. In addition, flange 205 of vent component 202 may abut against an interior side of the upwardly extending portion of projection 220. In particular embodiments, vent component 202, which has a uniform cross-section, may be provided in standard lengths and then cut to an appropriate size for fitting between side components 216 in building wall 106.

FIGS. 8A-8J depict a method for installation of moisture management system 100 including sill pan assembly 10, lower vent assembly 50 and upper vent assembly 200 into building wall 106 according to a particular embodiment of the invention. FIG. 8A shows horizontally-extending lower interior frame member 102, vertically-extending interior frame members 112 and horizontally-extending upper interior frame member 126. Together, interior frame members 102, 112, 126 define opening 104 in building wall 106. In the illustrated embodiment, opening 104 is a window opening.

Next, as shown in FIG. 8B, sheathing layer 120 is installed over interior frame members 102, 112, 126. In the illustrated embodiment, sheathing layer 120 comprises plywood together with a suitable building paper or building wrap, such as Tyvek™ marketed and sold by E. I. du Pont de Nemours and Company (Dupont), for example. In other embodiments, different sheathing materials may be used to form sheathing layer 120 or sheathing layer 120 may not be present at all. It will be appreciated by those skilled in the art that wall 106 may contain other materials (e.g. insulation, vapor barriers or the like) on an interior of sheathing layer 120. These optional other materials are not discussed herein as they are not germane to the explanation of the current invention.

FIG. 8C shows the next step, where corner components 11 of sill pan assembly 10 are cut to length and installed in window opening 104 by abutting side flanges 15 against interior vertical frame members 112, downwardly and upwardly-extending exterior flanges 12, 13 against sheathing layer 120 and base sections 14 against sill 102. Next, as shown in FIG. 8D, connector component 30 is installed between corner components 11 by snapping wing members 31 into notches 24 as discussed above (see also FIGS. 2, 3 and 4) to couple corner components 11 to one another and to complete the installation of sill pan assembly 10.

After installation of sill pan assembly 10, a window 107 may be installed in opening 104 as shown in FIG. 8E. In the illustrated embodiment, window 107 is bordered by a window frame 101 having upper window frame portion 101A, right side window frame portion 101B, lower window frame portion 101C and left side window frame portion 101D. Window 107 is installed by placing lower window frame portion 101C atop upper surfaces 22 of window-support members 20 and atop upper surfaces 40 of window-support members 38. As discussed above, upper surfaces 22, 40 of window-support members 20, 38 are oriented substantially horizontally, such that window 107 is oriented substantially vertically in window opening 104 despite the downward and outward angle of upper surfaces 17 of base sections 14 and upper surface 34 of base section 32. Thus, window 107 may be substantially vertically oriented while upper surfaces 17, 34 of base sections 14, 32 are capable of directing moisture away from interior 110 of building wall 106.

In the illustrated embodiment, each portion 101A, 101B, 101C, 101D of window frame 101 comprises a corresponding window flange 103A, 103B, 103C, 103D (together, window flange 103). Window 107 may be installed such that lower window flange portion 103C abuts against at least a portion of the exterior surfaces of spacers 26 and against at least a portion of exterior surface 46 of downwardly-extending exterior Flange 44. Portions of side window flange portions 103B, 103D and upper flange portion 103A may abut directly against sheathing layer 120. When window 107 is installed in window opening 104, spacers 26 provide window 107 with an orientation where window 107 extends slightly outwardly as it extends downwardly.

After installing window 107 (FIG. 8E), upper vent assembly 200 is assembled and installed in wall 106 as shown in FIG. 8F. More particularly, vent component 202 may be cut to length and coupled to side components 216 as discussed above and shown in FIG. 10A. Suitable adhesive may be used (e.g. on projections 220, 224 and/or on the sides of hood 203 and/or flange 205) to couple vent component 202 to side components 216. Upper vent assembly 200 may then be installed in wall 106 by placing stand off portion 209 of lower flange portion 208 atop upper window frame portion 101A (FIG. 11) and projecting suitable fasteners (not explicitly shown) through apertures 214 in upper flange portion 226 of flange 205 and into sheathing layer 120.

The next step in the construction of wall 106 is to create interstitial space 116 between sheathing layer 120 and external building layer 118. In general, interstitial space 116 need not necessarily be empty space. The purpose of interstitial space 116 is to allow for flow of air and/or moisture between sheathing layer 120 and external building layer 118 to vent the interior of wall 106. There are a variety of construction techniques used to create interstitial space 116. In the illustrated embodiment, interstitial space 116 is created by providing a layer of ventable material 132, such as (by way of non-limiting example) Home Slicker™ marketed and sold by Bejamin Obdyke Incorporated of Horsham, Pa., Delta Dry™ marketed and sold by Cosella-Dörken Products, Inc. of Beamsville, Ontario, Canada or the like. Ventable material 132 may be provided in rolls which are unwound, cut to size and fastened (e.g. by staples) to sheathing layer 120. In the illustrated embodiment, as shown in FIG. 8G, ventable material 132 is applied to sheathing layer 120 above window opening 104 (at 132A), on each side of window opening 104 (at 132B, 132C), below window opening 104 (at 132D) in a narrow swath and below window opening 104 (at 132E) in a full width swath.

Ventable material 132 applied at sides 132B,132C may abut against the exterior surfaces of side window flanges 103B, 103D. Ventable material 132 applied above window opening 104 (at 132A) may abut against the exterior surface of upper flange portion 226 of mounting flange 205. Ventable material 132 applied below window opening 104 (at 132D) may abut against the exterior surfaces of spacers 26 of downwardly-extending exterior flanges 12 and exterior surface 46 of downwardly-extending exterior flange 44. Ventable material 132 applied below window opening 104 (at 132E) may abut directly against sheathing 120. Application of ventable material 132 between sheathing 120 and external building layer 118 provides interstitial space 116 which allows for the flow of air and moisture therethrough.

In other embodiments, different techniques may be used to create interstitial space 116. Such techniques do not require the use of ventable material 132. For example, one relatively common technique involves creating columns or channels of interstitial space 116 by attaching vertically extending spacers (referred to as “furring strips” and/or “strapping”) to sheathing 120 at transversely spaced apart locations. These furring strips creates vertical columns of empty space 116 between sheathing 120 and external building layer 118. Still other systems for providing interstitial space 116 are known to those skilled in the art. The systems and methods of the invention should be understood to be applicable to any such techniques for creating an interstitial space 116 which allows for flow of air and moisture between sheathing layer 120 and external building layer 118.

As shown in FIG. 8H, the next step of the illustrated embodiment is to assemble lower vent assembly 50 by cutting vent component 52 to length and coupling the ends of vent component 52 to side components 54 as discussed above. A suitable adhesive may be used to help couple the ends of vent component 52 to side components 54 (e.g. at projections 77, 79 and/or at the ends of vent component 52). In the illustrated embodiment, the exterior surface of lower mounting portion 66 of vent flange 64 is mounted to a horizontally-extending lower exterior frame member 134B (FIG. 8H) prior to installation of lower vent assembly 50. Vent flange 64 may be mounted by projecting suitable fasteners through apertures 74, by projecting suitable fasteners though vent flange 64 and/or by suitable adhesive as discussed above.

Next, as shown in FIG. 8I, lower vent assembly 50 and horizontally-extending lower external frame member 134B (as assembled in FIG. 8H) are installed below window opening 104. To mount lower vent assembly 50 in wall 106, lower external horizontally-extending frame member 134B may be coupled by suitable fasteners (e.g. nails, screws, staples or the like) which extend into sheathing 120 through interstitial space 116. In addition or in the alternative, vertically-extending external frame members 122A, 122B (together, vertically-extending external frame members 122) maybe mounted on wall 106 (e.g. using suitable fasteners which project into sheathing 120 through interstitial space 116) and mounting flanges 76 of side components 54 may then abut against external vertically-extending frame members 122 and may be coupled thereto by suitable adhesive or fasteners. Horizontally-extending upper exterior frame member 134A may also be installed at this time, as shown in FIG. 8I.

Finally, as shown in FIG. 8J, external building layer 118 (shown as wood siding in the illustrated embodiment) may be applied over interstitial space 116 (e.g. ventable material 132 in the illustrated embodiment). In the illustrated embodiment, the uppermost piece of siding below window 107 may be cut to accommodate vertically-extending exterior frame members 122 and horizontally-extending lower exterior frame member 134B. Those skilled in the art will appreciate that many different types of wall constructions and window constructions are possible and that the wall construction and window construction shown in FIGS. 8A-8J and discussed above are merely representative examples of a wall construction and a window construction used to illustrate a method for installing moisture management system 100 including sill pan assembly 10, lower vent assembly 50 and upper vent assembly 200 according to a particular embodiment of the invention.

Sill pan assembly 10 and lower vent assembly 50 cooperate to manage moisture that would otherwise tend to accumulate in the vicinity of the bottom of window opening 104. Operation of sill pan assembly 10 and lower vent assembly 50 may be best understood with reference to FIG. 7. Sill pan assembly 10 protects wall 106 and more particularly, sill 102 by receiving moisture that drains downwardly from window 107 onto base sections 14 and base section 32. Upper surfaces 17 of base sections 14 and upper surface 34 of base section 32 are sloped downwardly and outwardly and therefore direct moisture received thereon away from interior 110 of wall 106 and toward downwardly-extending exterior flanges 12, 44. Moisture so directed reaches interstitial space 116 between sheathing 120 and external wall layer 118 where it is removed from wall 106 by the venting action facilitated by lower vent assembly 50.

Lower vent assembly 50 functions to provide ventilation to interstitial space 116 (i.e. to remove moisture therefrom), while simultaneously preventing excess moisture from entering interstitial space 116 from the exterior 108 of wall 106. Air is free to travel into and out of interstitial space 116 from the exterior 108 of wall 106 under hood 63 and through apertures 72. This air flow ventilates interstitial space 116 and tends to remove the moisture that is directed to interstitial space 116 by sill pan assembly 10 or otherwise. Apertures 72 are preferably sufficiently small to minimize (or at least impair) access to interstitial space 116 by insects or other pests. In addition to venting through apertures 72, hood 63 prevents excess moisture, such as from rain or snow, to enter interstitial space 116 through apertures 72. Rain or snow received on hood 63 is directed downwardly and outwardly toward an exterior 108 of building wall 106. As discussed above, the lowermost outer edge 65 hood 63 is exterior to external building layer 118. Optional drip flange 62 helps to cause moisture received on hood 63 to pool into drops and to drop away on the exterior 108 of wall 106.

The operation of upper vent assembly 200 may best be understood with reference to FIG. 11. Upper vent assembly 200 and more particularly apertures 210 of vent portion 211, provide a venting function for interstitial space 116 above window opening 104. Air flows through apertures 210 and into/out of interstitial space 116 above window opening 104. This air flow causes moisture in interstitial space 116 to evaporate and/or otherwise move out of interstitial space 116. Hood 203 also protects against moisture penetrating through cracks or the like in window opening 104. More particularly, hood 203 tends to direct moisture, such as from rain or snow, toward exterior 108 of building wall 106 to prevent such moisture from entering window opening 104.

As will be apparent to those skilled in the art in the light of the foregoing disclosure, many alterations and modifications are possible in the practice of this invention without departing from the spirit or scope thereof. For example:

-   -   In the embodiments described above, sill pan assembly 10         comprises a pair of corner components 11 which may be cut to         length and coupled to one another by connector component 30. In         other embodiments, sill pan assembly 10 may comprise a pair of         corner components 11 and one or more central components (which         may be similar in structure to base sections 14 and, optionally,         downwardly-extending exterior flanges 12 of corner components         11). Such embodiments may also comprise multiple connector         components 30 which join one corner component 11 to a central         component or which join a pair of central components to one         another. 

1. An apparatus for managing moisture in a vicinity of an opening in a building wall, the apparatus comprising: a sill pan mountable in the building wall atop a horizontally-extending lower frame member of the opening, the sill pan comprising a base section having an upper surface which slopes downwardly and outwardly from interior to a sheathing layer of the building wall to an interstitial space between the sheathing layer and an external building wall layer for directing moisture received thereon toward the interstitial space; a lower vent mountable in the building wall in a vicinity of a lower perimeter of the window opening, the lower vent comprising: a vent component which defines a plurality of lower vent apertures that provide fluid communication between an exterior of the building wall and the interstitial space; and a hood shaped to extend downwardly and outwardly from above the lower vent apertures and from interior to the exterior building wall layer to the exterior of the building wall.
 2. An apparatus according to claim 1 wherein the sill pan comprises a plurality of transversely spaced-apart window-support members having upper surfaces located above the upper surface of the base section and oriented substantially horizontally for receiving a lower portion of a window frame.
 3. An apparatus according to claim 2 wherein the sill pan comprises an exterior flange extending downwardly from the base section and abutting against an exterior surface of the sheathing layer and a plurality of transversely spaced-apart spacers having exterior surfaces that are located exterior to an exterior surface of the exterior flange and wherein at least a portion of the lower flange portion of the window frame abuts against the exterior surfaces of the spacers.
 4. An apparatus according to claim 3 wherein the sill pan comprises a plurality of transversely spaced-apart legs which extend downwardly from the base section to abut against an upper surface of the horizontally-extending lower frame member so that portions of the base section located between the transversely spaced-apart legs are vertically spaced-apart from the upper surface of the horizontally-extending lower frame member.
 5. An apparatus according to claim 4 wherein the sill pan comprises a pair of corner components, each corner component formed from a monolithic piece of material and each corner component comprising: a corner base section mountable atop the horizontally-extending lower frame member of the opening to provide at least a portion of the base section; one or more corner window-support members having upper surfaces located above the upper surface of the corner base section to provide one or more of the window-support members; a corner exterior flange extending downwardly from the corner base section and abutting against the exterior surface of the sheathing layer to provide at least a portion of the exterior flange; one or more corner spacers having exterior surfaces that are located exterior to an exterior surface of the corner exterior flange to provide one or more of the spacers; and one or more corner legs which extend downwardly from the corner base section to provide one or more of the legs.
 6. An apparatus according to claim 5 wherein each corner component comprises: a side flange which extends upwardly from the corner base section to abut against a corresponding side of a corresponding vertically-extending frame member of the opening; and an upwardly-extending exterior flange which extends upwardly and transversely away from the corner base section to abut against one of: the exterior surface of the sheathing layer; and a corresponding exterior surface of the corresponding vertically-extending frame member.
 7. An apparatus according to claim 6 wherein, for each corner component, the side flange comprises a portion which extends below the corner base section to abut against the upper surface of the horizontally-extending lower frame member.
 8. An apparatus according to claim 5 wherein the sill pan comprises a connector component for connecting to both of the corner components, the connector component comprising a connector base section mountable atop the horizontally-extending lower frame member of the opening to provide at least a portion of the base section.
 9. An apparatus according to claim 8 wherein the connector component comprises one or more connector window-support members having upper surfaces located above the upper surface of the connector base section to provide one or more of the window-support members.
 10. An apparatus according to claim 8 wherein the connector component comprises: a connector exterior flange that extends downwardly from the connector base section and abuts against the exterior surface of the sheathing layer; one or more connector spacers having exterior surfaces that are located exterior to an exterior surface of the connector exterior flange to provide one or more of the spacers; and one or more connector legs which extend downwardly from the corner base section to provide one or more of the legs.
 11. An apparatus according to claim 8 wherein the connector component comprises a pair of wings that extend from the connector base section in transversely opposing directions and each corner component comprises one or more notches for receiving a corresponding one of the wings to form a resilient snap-together coupling between the corresponding one of the wings of the connector component and the one or more notches of each corner component.
 12. An apparatus according to claim 11 wherein each of the one or more notches of each corner component is located in a corresponding one of the corner window-support members.
 13. An apparatus according to claim 1 wherein the hood comprises: an upper hood portion that extends outwardly and downwardly from above the lower vent apertures and from a vertically and transversely-extending lower window flange on the lower portion of the window frame located interior to the exterior building wall layer; and an exterior hood portion that extends outwardly and downwardly from an outermost extent of the upper hood portion to the exterior of the building wall and wherein the exterior hood portion extends more sharply downwardly than the upper hood portion.
 14. An apparatus according to claim 13 wherein the exterior hood portion comprises a drip flange at its outermost and lowermost end, the drip flange also extending downwardly and outwardly and wherein the drip flange extends downwardly more sharply than the upper hood portion and less sharply than a remainder of the exterior hood portion and wherein the lowermost edge of the drip flange is located below the lower vent apertures.
 15. An apparatus according to claim 13 wherein the vent component and the hood are integrally formed from a single monolithic piece of material.
 16. An apparatus according to claim 1 comprising an upper vent mountable in the building wall in a vicinity of an upper perimeter of the opening, the upper vent comprising an upper vent component which defines a plurality of upper vent apertures that provide fluid communication between the exterior of the building wall and the interstitial space located above the window; and an upper vent hood shaped to extend downwardly and outwardly from interior to the exterior building wall layer to the exterior of the building wall.
 17. An apparatus according to claim 16 wherein the upper vent hood is located below the upper vent apertures.
 18. An apparatus according to claim 6 wherein the sill pan also comprises one or more central components, each central component comprising: a central base section mountable atop the horizontally-extending lower frame member of the opening to provide at least a portion of the base section; and one or more central window-support members having upper surfaces located above the upper surface of the central base section to provide one or more of the window-support members.
 19. An apparatus according to claim 18 wherein each central component comprises: a central exterior flange extending downwardly from the central base section and abutting against the exterior surface of the sheathing layer to provide at least a portion of the exterior flange; one or more central spacers having exterior surfaces that are located exterior to an exterior surface of the central exterior flange to provide one or more of the spacers; and one or more central legs which extend downwardly from the central base section to provide one or more of the legs.
 20. An apparatus according to claim 18 wherein the sill pan comprises a connector component for connecting one of the corner components to one of the central components, the connector component comprising a connector base section mountable atop the horizontally-extending lower frame member of the opening to provide at least a portion of the base section.
 21. An apparatus according to claim 20 wherein the connector component comprises A pair of wings that extend from the connector base section in transversely opposing directions, wherein the one of the corner components comprises one or more notches in one or more of their corresponding corner window-support members for receiving a corresponding one of the wings and forming a resilient snap-together coupling therebetween and wherein the one of the central components comprises one or more notches in one or more of their corresponding central window-support members for receiving a corresponding one of the wings and forming a resilient snap-together coupling therebetween.
 22. An apparatus for managing moisture in a vicinity of a window opening in a building wall, the apparatus comprising: a pair of corner components, each corner component comprising: a corner base section mountable atop a horizontally-extending lower frame member of the window opening and having an upper surface which slopes downwardly and outwardly from interior of a sheathing layer of the building wall to an interstitial space between the sheathing layer and an external building wall layer for directing moisture received thereon toward the interstitial space; a plurality of transversely spaced-apart corner window support members having upper surfaces located above the upper surface of the corner base section and oriented substantially horizontally for receiving a lower portion of a window frame; a corner exterior flange extending downwardly from the corner base section and abutting against an exterior surface of sheathing layer; and a plurality of transversely spaced-apart corner spacers having exterior surfaces that are located exterior to an exterior surface of the corner exterior flange and wherein at least a portion of the window frame abuts against the exterior surfaces of the corner spacers; and a connector component for connecting to both of the corner components, the connector component comprising a connector base section and a pair of wings that extend from the connector base section in transversely opposing directions to form snap-together couplings between a corresponding one of the wings and one or more notches on each of the corner components.
 23. An apparatus according to claim 22 comprising a lower vent mountable in the building wall in a vicinity of a lower perimeter of the window opening, the lower vent comprising: a vent component which defines a plurality of lower vent apertures that provide fluid communication between an exterior of the building wall and the interstitial space; and a hood shaped to extend downwardly and outwardly from above the lower vent apertures and from interior to the exterior building wall layer to the exterior of the building wall.
 24. A method for managing moisture in a vicinity of a window opening of a building wall, the method comprising: creating an interstitial space between a sheathing layer of the building wall and an external building wall layer; mounting a sill pan in the building wall atop a horizontally-extending lower frame member of the window opening, the sill pan comprising: a base section having an upper surface which slopes downwardly and outwardly from a location interior to the sheathing layer to the interstitial space for directing moisture received thereon toward the interstitial space; and a plurality of transversely spaced-apart window-support members having substantially horizontally oriented upper surfaces located above the upper surface of the base section; installing a window in the window opening such that at least part of lower portion of the window frame is positioned atop the upper surfaces of the window-support members; mounting a lower vent in the building wall in a vicinity of a lower perimeter of the window opening, the lower vent comprising: a vent component which defines a plurality of lower vent apertures that provide fluid communication between an exterior of the building wall and the interstitial space; and a hood shaped to extend downwardly and outwardly from above the lower vent apertures and from interior to the exterior building wall layer to the exterior of the building wall; and applying the external building wall layer to the building wall, the external building wall layer overlapping a lower portion of the vent component below the lower vent apertures.
 25. A method according to claim 24 comprising mounting an upper vent in the building wall in a vicinity of an upper perimeter of the window opening, the upper vent comprising an upper vent component which defines a plurality of upper vent apertures that provide fluid communication between the exterior of the building wall and the interstitial space located above the window; and an upper vent hood shaped to extend downwardly and outwardly from interior to the exterior building wall layer to the exterior of the building wall. 